Best Strategy Software for Mac User

I'm a mac user and currently trade through the ThinkorSwim desktop trade platform. I want to be able to create some multi day trade strategies using technical analysis and then run a backtest.

I'm mostly after very simply moving average crossovers and less involved ideas, so no learning C+ if I can avoid it.

I've tried using ThinkorSwim's scripting tools, but they are lacking, as is a library of script examples which a newbe can pull from. Any suggestions pointing me toward the best software/broker option would be appreciated.